This invention relates to a system for the diffuse ventilation of a vehicle interior in the area of a dashboard extending along the windshield having a top part visible to the vehicle occupants which has a plurality of air outlet openings, and having a bottom part which is covered by the top part and which, together with the top part, bounds an air distribution space connected to an air feeding device.
In the case of a known ventilation system of this type (German Patent Document DE-GM 1 909 519), the top part is formed by the dashboard or the instrument panel itself and the air feeding device is connected, by way of a connection opening arranged in the center of the bottom part, with the air distribution space enclosed by the top part and the bottom part. The top part is manufactured corresponding to the desired contour of the dashboard or of the instrument panel and is very arched in the forward area pointing toward the seats. As a result, the air outlet holes situated in this area have hole axes which are sloped with respect to the vertical line.
In the case of the construction of the dashboard or the instrument panel customary today consisting of a rigid support, a foamed material (PU foam) covering the support, and of a deep-drawn surface foil covering the foamed material, the perforation of the dashboard results in considerable problems with respect to manufacturing techniques so that the described ventilation system cannot be implemented in series at reasonable cost.
It is an object of the invention to provide a ventilation system for the diffuse ventilation of the initially mentioned type for the dashboard area which, while the conventional structure of the dashboard is not changed, significantly simplifies the manufacturing and ensures a uniform, draft-free diffuse ventilation while at the same time reducing the heat radiation of the dashboard caused by the radiation of the sun.
In the case of a ventilation system for a diffuse ventilation of the type referred to above, this object is achieved according to the invention by providing an arrangement wherein the top part and the bottom part are connected to form an insert which is disposed in the dashboard and is flush with its top side, and wherein a plurality of separate channels are formed in the bottom part which are parallel with respect to one another, are open toward the top, extend in the longitudinal direction of the insert and are covered directly by the top part.
According to the invention, the housing according to the invention of the air distribution space for the diffuse ventilation in a separate insert which is flush with the surface of the dashboard or of the instrument panel, permits the manufacturing of the ventilation system according to freely selectable manufacturing processes whose selection is not limited by the preset structure of the dashboard. The insert as well as the dashboard with the required recess for receiving the insert are manufactured separately, in which case the manufacturing criteria may be selected independently of one another according to cost aspects. The providing of the separate channels in the bottom part, on the one hand, increases the stiffness of the insert and, on the other hand, permits a better control of the diffuse air flow during the exit from the insert in that, by means of the channel system, a uniform pressure drop is achieved with respect to the whole volume of the air distribution space.
Furthermore, the insert which is separate from the dashboard has mounting advantages because the accessibility of parts below the insert in the area of the dashboard is significantly improved.
Advantageous embodiments of the ventilation system according to the invention with expedient developments and further developments of the invention are described herein.
According to a preferred embodiment of the invention, several hole areas with a different hole pattern are arranged behind one another viewed in the longitudinal course of the top part, thus transversely to the longitudinal axis of the vehicle. By means of the appropriate construction of the hole patterns in the individual hole areas, the air distribution and a noise optimization are made uniform while the diffuse ventilation is maximal. For any surface design of the dashboard to which the shape of the insert must be adapted, Such an optimization can be carried out by a corresponding construction of the hole patterns in the different hole areas, that is, by determining the number of holes, the hole diameter and the slope of the hole axes with respect to the surface of the top part. The construction of the hole patterns is dependent on adjacent points of the bottom part and the configuration of connection openings for the air feeding device provided in the bottom part.
In an embodiment of the invention in which the connection opening for the air feeding device is arranged in the center of the bottom part, the holes situated in the center hole area of the top part have the smallest hole diameter and, originating from this hole area, at both sides toward the outside, additional hole areas adjoin, preferably mirror symmetrically to the first hole area. The holes of these additional hole areas, within the respective hole area, have a constant hole diameter which increases, however, from hole area to hole area, the holes situated in the two exterior hole areas located next to the ends of the top part having the largest hole diameter.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.